Comparative mass spectrometric and immunoassay-based proteome analysis in serum of Duchenne muscular dystrophy patients

Purpose: Duchenne muscular dystrophy (DMD) is a severe and fatal neuromuscular disease. With the current developments on novel therapeutic strategies for DMD, the need to carefully monitor disease progression or regression upon treatment using molecular markers has become urgent. Experimental design: 2D LC protein fractionation was performed on patient serum samples, followed by LC-MS/MS-based identifications with label-free quantifications. Results: Protein signatures were compared between patients and healthy (child and adult) controls and between ambulant and nonambulant patients. Various myofibrillar proteins demonstrated differences between DMD patients and controls, likely due to leakiness and breakdown of muscle fibers. Previously reported biomarkers, such as muscle-derived titin, myosin, and carbonic anhydrase I (CA1), were verified. MS-based results were compared with ELISA for vitamin D binding protein (GC), fibulin-1 (FBLN1), gelsolin (GSN), and carbonic anhydrase 1 (CA1). Conclusions and clinical relevance: The combined results of MS-and ELISA-based quantifications indicated more studies are needed to validate this serum protein signature for DMD patients. With these data promising candidate biomarkers have been identified for a rare genetic disease using serum proteome analysis.